1. Field of the Invention
The present invention pertains to a hollow glass product and a process of manufacturing the same.
2. Description of the Background
The traditional processes that are extensively used at the present time to fabricate the aforementioned products utilize so-called I.S. (Individual Section) machines and are known under the names of “blown-blown” and “press-blown” processes. During the first stage of these traditional processes, a ball or drop of glass is introduced into a roughing mold and shaped into a form of a rough mold. The base of the roughing mold is extended by a collar mold used for shaping an upper opening part of a product to be fabricated in the rough mold.
The collar mold also has the function of gripping the rough mold in a subsequent operation of turning over the rough mold prior to the second stage in which the roughing mold is replaced by a finishing mold. In the finishing mold, the rough mold is shaped into a final hollow product by blowing.
Among the processes currently being used, the “blown-blown” process can be broken down into the following stages:                loading: a drop or ball of glass enters due to the effect of its own weight into a first mold (a roughing mold) through its upper end which corresponds to the bottom of a final product such as a bottle, etc.;        compression: after loading, a rough bottom section closes the roughing mold; then a blast of compressed air forces the drop of glass in the roughing mold through the intermediary of the roughing mold into the lower part of the mold in which a collar of the final product is later formed; this compression also ensures good thermal contact between the drop of glass and the roughing mold;        perforation: a punch of small dimensions, taking up approximately the height of the collar and fitted at the lower part of the roughing mold, detaches from the lower part of the roughing mold, thereby leaving room for compressed air to be delivered, the compressed air pushes in front of it the hot, less viscous glass located in the vicinity of the axis of the roughing mold, while the more viscous cold glass that has been cooled upon contact with the mold remains in place; a blank or a rough mold of the final product is thereby produced;        transfer: when the blank is sufficiently cooled in the roughing mold for handling, the blank is transferred into a second mold (a finishing mold) which has a shape of the final product;        elongation and blowing: once the blank is placed in the finishing mold, the blank is allowed to lengthen for a certain amount of time before blowing in order to give the shape of the product; this lengthening stage allows the glass to be distributed throughout the product;        extraction: upon contact with the finishing mold, the glass cools quickly, and when its viscosity is sufficiently low, the product is extracted from the finishing mold.        
The “press-blown” process differs from the “blown-blown” process only in the phase of shaping a blank or rough mold. In the “press-blown” process, a blank is obtained by compression of the glass in the closed roughing mold by means of a more or less lengthy punch that penetrates into the mold in the bottom of the latter through the collar mold. There are therefore no compression or perforation stage, and the opening of the product is formed in a single operation by this pressing.
These processes allow one to make products with shapes that are axisymmetrical or not. The device, which is used here as indicated above, comprises only one section of an individual section machine, which has several of them.